Recent innovations in passenger travel in and around buildings, as well as incidental movement of freight, have provided transport systems employing cabs which can be transferred between a variety of locomotive devices. For instance, in U.S. patent application Ser. No. 08/749,296, filed Nov. 14, 1996, there is disclosed a system in which passengers can ride from an upper floor in one building downwardly to a ground level, and then horizontally for some distance, and then vertically in another building, all within the same passenger cab. In that case, the passenger cab is transferred from elevator car frames to horizontal transfer bogies and then to other elevator car frames. In such cases, the smooth transfer of the cab from one platform to another, such as from one car frame to another car frame, or from a car frame to a bogie, is essential for a successful system. In commonly owned, copending U.S. patent application Ser. No. 08/749,120, a system for transferring a cab between an elevator car frame and a bogie is disclosed. In that system, the bogie travels directly toward the elevator car frame, and thereby presents the tips of cab rails on the bogie directly into contact with tips of cab rails on the elevator car frame. However, in many applications, a bogie should travel across the front of an elevator hatchway, rather than into it. In such a case, the bogie cannot present its cab rails directly to the cab rails on an elevator car frame.
In U.S. Pat. No. 5,657,835, elevator cabs are transferred from an elevator car frame in a lower hoistway to an elevator car frame in a higher hoistway which is adjacent thereto. In that system, the cabs either simply roll across a sill, or they may be transferred by means of a rack and pinion arrangement disclosed therein. However, it would be preferable to provide rails for the cab to ride on. Of course, elevator car frames must have clearance between themselves and the adjacent building structures.